For his entire life, Sergio Peralta dreamed about playing catch. When he was born, Peralta said his right arm didn't fully develop; instead, he grew tiny fingers at the end of his arm. So, he learned to do everyday activities with one hand. Over the years, the 15-year-old had lost hope that would change. But after he enrolled at a new high school last fall, engineering students there built him a prosthetic hand – a gesture the sophomore said has changed his life. Now, he can not only toss a ball but also carry water bottles, cups and food with his right hand. The project started when computer science teacher Jeff Wilkins noticed Peralta was the only student who moved his mouse to the left side of his keyboard. He then saw that Peralta didn't have a right hand. A few years earlier, Wilkins had started an engineering program at the school so students could take on projects that improve their community. When he learned about Peralta's hand, he had the idea to make a 3-D printed prosthetic hand. The product the students created has changed Peralta's life. "I want to teach them that products don't have to be about making money. They can be about making someone else have a more fruitful life," said Wilkins.